The question of whether Bitcoin’s 21 million supply cap is truly immutable has resurfaced after BlackRock released a three-minute explainer video on Dec. 17. The video included a disclaimer suggesting there’s no guarantee the cap won’t be altered.

Bitcoin’s fixed supply is a cornerstone of its value as a store of wealth, and any change could fundamentally impact its perception among investors.

In the video, BlackRock highlighted Bitcoin’s 21 million cap, noting it as a “hard-coded rule” that controls supply, purchasing power, and prevents excessive currency creation. However, the disclaimer stated: “There is no guarantee that Bitcoin’s 21 million supply cap will not be changed.”

MicroStrategy chairman Michael Saylor reposted the video, sparking criticism. Joel Valenzuela, Dashpay’s marketing director, commented, “When the supply cap increase happens, it will have ‘always been part of the plan.’ And today, in 2024, people have the audacity to say Bitcoin wasn’t hijacked.”

Ethereum developer Antiprosynthesis added, “BlackRock understands Bitcoin better than Bitcoiners.”

Is Bitcoin’s Supply Cap Changeable?

Bitcoin developer Super Testnet, known for BitVM, explained that altering Bitcoin’s supply cap would depend on how one defines “Bitcoin.”

In theory, the cap could change if a majority of the community—node operators, developers, miners, and investors—reached consensus on a hard fork. Such a change would involve a proposal to gauge consensus, followed by implementing changes in Bitcoin Core.

If most node operators and miners adopted the new fork, it would create a “new” Bitcoin network with an uncapped supply. However, Super Testnet argued that this new chain wouldn’t truly be Bitcoin.

“The inflation cap is definitional to Bitcoin,” they said. “Eliminate that, and whatever you have isn’t Bitcoin anymore. You might as well ask what it would take to turn Bitcoin into PayPal.”

In essence, an uncapped version wouldn’t be Satoshi Nakamoto’s Bitcoin.